As automobiles using gasoline as their fuel exhaust carbon dioxide CO2, hydrogen is focused as a substitute fuel. The hydrogen, however, is an inflammable substance and has high explosive power. Accordingly, its storage requires a lot of caution. To solve the problem, a technique for storing hydrogen as a hydrogenation fuel and if necessary, taking out hydrogen gas by using chemical reaction to supply it to the automobiles are disclosed in Japanese laid open patent publications No. 2005-299499 and 2005-147124.